SEAL FOR HARDWARE SEGMENTS
The present disclosure is directed to a shroud assembly for a gas turbine engine that includes a first shroud segment, a second shroud segment spaced from the first shroud segment, and a third shroud segment spaced from the first shroud segment. The first and the second shroud segments define a gap therebetween, and the first and the third shroud segments define a gap therebetween. A first seal portion is positioned at least partially on the first and the third shroud segments and at least partially covers the gap defined by the first and the third shroud segments. A second seal portion is positioned at least partially on the first and the second shroud segments and at least partially covers the gap defined by the first and the second shroud segments. A third seal portion extends between and couples the first and the second seal portions.
The present disclosure relates to a gas turbine engine. More specifically, the present disclosure relates to seal for use in a gas turbine engine.
BACKGROUND OF THE INVENTIONA gas turbine engine generally includes, in serial flow order, a compressor section, a combustion section, a turbine section, and an exhaust section. In operation, air enters an inlet of the compressor section where one or more axial compressors progressively compress the air until it reaches the combustion section. Fuel mixes with the compressed air and burns within the combustion section, thereby creating combustion gases. The combustion gases flow from the combustion section through a hot gas path defined within the turbine section and then exit the turbine section via the exhaust section.
In particular configurations, the turbine section includes, in serial flow order, a high pressure turbine and a low pressure turbine. The high pressure and the low pressure turbines each include one or more rows of turbine blades, which extract kinetic energy and/or thermal energy from the combustion gases flowing therethrough. A turbine shroud typically forms a ring or enclosure around each row of turbine blades. That is, each turbine shroud is positioned radially outwardly from and circumferentially encloses each corresponding row of turbine blades.
Typically, each turbine shroud is formed from a plurality of shroud segments, which are assembled to form the ring that circumferentially encloses the corresponding row of turbine rotor blades. In this respect, gaps may exist between each of the shroud segments. These gaps may permit a portion of the combustion gases to escape therebetween, which may reduce the efficiency of the gas turbine engine. Accordingly, a seal that reduces the amount of combustion gases escaping through gaps between adjacent shroud segments would be welcomed in the technology.
BRIEF DESCRIPTION OF THE INVENTIONAspects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.
In one aspect, the present disclosure is directed to a shroud assembly for a gas turbine engine that defines a circumferential direction C. The shroud assembly includes a first shroud segment that extends between a first end and a second end along the circumferential direction C. A second shroud segment is spaced from the first shroud segment along the circumferential direction C and defines a gap with the first end of the first shroud segment. A third shroud segment is spaced from the first shroud segment along the circumferential direction C and defines a gap with the second end of the first shroud segment. The shroud assembly also includes a seal having a first seal portion positioned at least partially on the first shroud segment and the third shroud segment and at least partially covering the gap defined by the first shroud segment and the third shroud segment. A second seal portion is positioned at least partially on the first shroud segment and the second shroud segment and at least partially covers the gap defined between the first shroud segment and the second shroud segment. A third seal portion extends between and couples the first seal portion and the second seal portion.
A further embodiment of the present disclosure is directed to a gas turbine engine that defines a circumferential direction C. The gas turbine engine includes a compressor section, a combustion section, and a turbine section. A first shroud segment extends between a first end and a second end along the circumferential direction C. A second shroud segment is spaced from the first shroud segment along the circumferential direction C and defines a gap with the second end of the first shroud segment. A third shroud segment is spaced from the first shroud segment along the circumferential direction C and defines a gap with the first end of the first shroud segment. The gas turbine engine also includes a seal having a first seal portion positioned at least partially on the first shroud segment and the third shroud segment and at least partially covering the gap defined by the first shroud segment and the third shroud segment. A second seal portion is positioned at least partially on the first shroud segment and second shroud segment and at least partially covers the gap defined between the first shroud segment and the second shroud segment. A third seal portion extends between and couples the first seal portion and the second seal portion.
These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.
A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended FIGS., in which:
Repeat use of reference characters in the present specification and drawings is intended to represent the same or analogous features or elements of the present invention.
DETAILED DESCRIPTION OF THE INVENTIONReference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.
As used herein, the terms “first”, “second”, and “third” may be used interchangeably to distinguish one component from another and are not intended to signify location or importance of the individual components.
The terms “upstream” and “downstream” refer to the relative direction with respect to fluid flow in a fluid pathway. For example, “upstream” refers to the direction from which the fluid flows, and “downstream” refers to the direction to which the fluid flows.
Referring now to the drawings, wherein identical numerals indicate the same elements throughout the figures,
The gas turbine engine 14 may generally include a substantially tubular outer casing 18 that defines an annular inlet 20. The outer casing 18 may be formed from multiple casings. The outer casing 18 encases, in serial flow relationship, a compressor section having a booster or low pressure compressor 22 (“LP compressor 22”) and a high pressure compressor 24 (“HP compressor 24”), a combustor 26, a turbine section having a high pressure turbine 28 (“HP turbine 28”) and a low pressure turbine 30 (“LP turbine 30”), and a jet exhaust nozzle section 32. A high pressure shaft or spool 34 (“HP spool 34”) drivingly connects the HP turbine 28 to the HP compressor 24. A low pressure shaft or spool 36 (“LP spool 36”) drivingly connects the LP turbine 30 to the LP compressor 22. The LP spool 36 may also connect to a fan spool or shaft 38 (“fan spool 38”) of the fan section 16. In particular embodiments, as shown in
As shown in
The turbine rotor blades 58, 68 extend radially outwardly from and are coupled to the HP spool 34 (
As shown in
Each turbine shroud 72(a), 72(b) may radially be spaced apart from one or more corresponding blade tips 76, 78 of the turbine rotor blades 58, 68. One or more pins (not shown) may couple each turbine shroud 72(a), 72(b) to a corresponding turbine shroud mount 84(a), 84(b). The turbine shroud mount 84(a), 84(b) may connect to a casing 82 of the turbofan 10.
This arrangement forms clearance gaps between the blade tips 76, 78 and sealing surfaces or hot side surfaces 80(a), 80(b). As mentioned above, it is generally desirable to minimize the clearance gap between the blade tips 76, 78 and the turbine shrouds 74(a), 74(b), particularly during cruise operation of the turbofan 10, to reduce leakage from the hot gas path 70 over the blade tips 76, 78 and through the clearance gaps. In particular embodiments, at least one of the turbine shrouds 74(a), 74(b) may be formed as a continuous, unitary, or seamless ring.
As illustrated in
The combustion gases 210 flow through the HP turbine 28 where the stator vanes 54, 64 and turbine rotor blades 58, 68 extract a first portion of kinetic and/or thermal energy from the combustion gases 210. This energy extraction supports operation of the HP compressor 24. The combustion gases 210 then flow through the LP turbine 30 where sequential stages of LP turbine stator vanes 212 and LP turbine rotor blades 214 coupled to the LP spool 36 extract a second portion of thermal and/or kinetic energy from the combustion gases 210. This energy extraction causes the LP spool 36 to rotate, thereby supporting operation of the LP compressor 22 and/or rotation of the fan spool 38. The combustion gases 210 then flow through the jet exhaust nozzle section 32 of the gas turbine engine 14.
Along with the turbofan 10, the core turbine 14 serves a similar purpose and sees a similar environment in land-based gas turbines, turbojet engines in which the ratio of the first portion of air 204 to the second portion of air 206 is less than that of a turbofan, and unducted fan engines in which the fan section 16 is devoid of the nacelle 42. In each of the turbofan, turbojet, and unducted engines, a speed reduction device (e.g., the reduction gearbox 39) may be included between any shafts and spools. For example, the reduction gearbox 39 may be disposed between the LP spool 36 and the fan spool 38 of the fan section 16.
As illustrated in
The shroud assembly 100 may correspond with or be installed in place of any of the shrouds 74(a), 74(b). Accordingly, the shroud assembly 100 may be incorporated into the HP turbine 28 shown in
Referring now particularly to
The first shroud segment 102(a) also includes a first mounting projection 118(a) for coupling the first shroud segment 102(a) to, e.g., the casing 82 (
The second shroud segment 102(b) also includes a second mounting projection 118(b) for coupling the second shroud segment 102(b) to, e.g., the casing 82. In the embodiment shown in
Furthermore, as is also illustrated in
As shown in
The seal 124 reduces the amount of combustion gases 210 that escapes from the hot gas path 70 between the first, the second, and the third shroud segments 102(a), 102(b), 102(c). As mentioned above, the first, the second, and the third shroud segments 102(a), 102(b), 102(c) are spaced apart along the circumferential direction C by the gaps 116. The seal 124 may be planar and positioned on the radially outer surfaces 106(a), 106(b), 106(c) of the first, the second, and the third shroud segments 102(a), 102(b), 102(c). In this respect, the seal 124 bridges the gaps 116 between the first, the second, and the third shroud segments 102(a), 102(b), 102(c), thereby reducing the volume of combustion gases 210 that escape therebetween.
More particularly, the first seal portion 126 includes a first circumferential edge 132 and a second circumferential edge 134 spaced apart along the circumferential direction C from the first circumferential edge 132. Similarly, the second seal portion 126 includes a first circumferential edge 136 and a second circumferential edge 138 spaced apart along the circumferential direction C from the first circumferential edge 136. The third seal portion 130 includes a first axial edge 140 and a second axial edge 142 spaced apart along the axial direction A from the first axial edge 140. The first circumferential edge 132 of the first seal portion 126 is positioned circumferentially between the first and the second circumferential surfaces 112(c), 114(c) of the third shroud segment 102(c). The second circumferential edge 134 of the first seal portion 126 is positioned circumferentially between the first and the second circumferential surfaces 112(a), 114(a) of the first shroud segment 102(a). The first circumferential edge 136 of the second seal portion 128 is positioned circumferentially between the first and the second circumferential surfaces 112(b), 114(b) of the second shroud segment 102(b). The second circumferential edge 138 of the second seal portion 128 is positioned circumferentially between the first and the second circumferential surfaces 112(a), 114(a) of the first shroud segment 102(a).
The first and the second circumferential edges 132, 134, 136, 138 of the first and the second seal portions 126, 128 are all positioned in parallel planes. The first and the second axial edges 140, 142 of the third seal portion 130 are positioned in planes perpendicular to the planes in which the first and the second circumferential edges 132, 134, 136, 138 of the first and the second seal portions 126, 128 are positioned. In this respect, the first, the second, and the third seal portions 126, 128, 130 give the seal 124 a “U” shape in some embodiments. Nevertheless, the seal 124 may have any suitable configuration.
As mentioned above, the seal 124 is positioned on the radially outer surfaces 106(a), 106(b), 106(c) of the first, the second, and the third seal segments 102(a), 102(b), 102(c). As best illustrated in
In other exemplary embodiments, the first, the second, and/or the third mounting plates 120(a), 120(b), 120(c) extend to the first and the second circumferential surfaces 112(a), 112(b), 112(c), 114(a), 114(b), 114(c) of the first, the second, and/or the third shroud segments 102(a), 102(b), 102(c). In these embodiments, slots (not shown) may be formed in the first, the second, and/or the third mounting plates 120(a), 120(b), 120(c) to provide clearance for the first and the second seal portions 126, 128. Preferably, these slots extend axially through the entirety of the mounting plates 120(a), 120(b), 120(c). That is, the slots are open on both axial sides of the mounting plates 120(a), 120(b).
In the embodiment shown in
The shroud segments 102(a), 102(b), 102(c), etc. in the shroud assembly 100 form a ring that circumferentially encloses one of the rows 56, 66 of turbine blades 58, 68 (
As mentioned above,
The seals 124 may be constructed from a suitable nickel or cobalt alloys. Suitable nickel and cobalt alloys include RENE 41® Alloy produced by General Electric Co. of Schenectady, N.Y., USA; HAYNES® alloy 188 produced by Haynes International of Kokomo, Ind., USA; and UDIMET® alloy L-605 produced by Special Metal Corporation of New Hartford, N.Y., USA. Nevertheless, any suitable metallic material may be used.
In some embodiments, the seals 124 may be a ceramic matrix composite (“CMC”) material. The CMC material used may be a continuous fiber reinforced CMC material. For example, suitable continuous fiber reinforced CMC materials may include CMC materials reinforced with continuous carbon fibers, oxide fibers, silicon carbide monofilament fibers, and other CMC materials including continuous fiber lay-ups and/or woven fiber preforms. In other embodiments, the CMC material used may be a discontinuous reinforced CMC material or unreinforced silicon carbide slurry matrix plies. For instance, suitable discontinuous reinforced CMC materials may include particulate, platelet, whisker, chopped fiber, weave, braid, in situ, and nano-composite reinforced CMC materials.
The shroud assembly 100 is described above in the context of being positioned circumferentially around the rows 56, 66 of the turbine blades 58, 68 in the HP turbine 28. Nevertheless, the shroud assembly 100 may be positioned circumferentially around any row of turbine blades in the HP turbine 28. Moreover, the shroud assembly 100 may be positioned in the LP turbine 30, the LP compressor 22, or the HP compressor 24. Furthermore, the seal 124 may be used independently of the shroud assembly 100. For example, the seal 124 may be used in connection with the rows 52, 62 of stator vanes 54, 64.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
Claims
1. A shroud assembly for a gas turbine engine defining a circumferential direction C, comprising:
- a first shroud segment extending between a first end and a second end along the circumferential direction C;
- a second shroud segment spaced from the first shroud segment along the circumferential direction C and defining a gap with the first end of the first shroud segment;
- a third shroud segment spaced from the first shroud segment along the circumferential direction C and defining a gap with the second end of the first shroud segment; and
- a seal comprising: a first seal portion positioned at least partially on the first shroud segment and the third shroud segment and at least partially covering the gap defined by the first shroud segment and the third shroud segment; a second seal portion positioned at least partially on the first shroud segment and the second shroud segment and at least partially covering the gap defined between the first shroud segment and the second shroud segment; and a third seal portion extending between and coupling the first seal portion and the second seal portion.
2. The shroud assembly of claim 1, wherein the first shroud segment comprises a first circumferential surface at the first end and a second circumferential surface at the second end, wherein the first seal portion comprises a first circumferential edge and a second circumferential edge spaced apart along the circumferential direction C, and wherein the first circumferential surface of the first shroud segment is positioned circumferentially between the first circumferential edge of the first seal portion and the second circumferential edge of the first seal portion.
3. The shroud assembly of claim 1, wherein the second seal portion comprises a first circumferential edge and a second circumferential edge spaced apart along the circumferential direction, wherein the second circumferential surface of the first shroud segment is positioned circumferentially between the first circumferential edge of the second seal portion and the second circumferential surface of the edge seal portion.
4. The shroud assembly of claim 1, wherein the first shroud segment comprises a radially inner surface and a radially outer surface spaced apart from the radially inner surface, and wherein the seal is positioned on the radially outer surface of the first shroud segment.
5. The shroud assembly of claim 4, further comprising:
- a mounting projection extending radially outwardly from the radially outer surface of the first shroud segment, wherein the mounting projection is circumferentially positioned between the second circumferential edge of the first seal portion and the second circumferential edge of the second seal portion.
6. The shroud assembly of claim 1, wherein the seal comprises a wall projecting radially outwardly from the third seal portion.
7. The shroud assembly of claim 1, wherein the first shroud segment comprises a first axial surface and second axial surface spaced apart along the axial direction A from the first axial surface, wherein the third seal portion comprises a first axial surface and second axial surface spaced apart along the axial direction A from the first axial surface, and wherein the first axial surface of the first shroud segment is positioned axially between the first axial surface of the third seal portion and the second axial surface of the third seal portion.
8. The shroud assembly of claim 7, wherein the second axial surface of the third seal portion is perpendicular to the second circumferential surface of the first seal portion and the second circumferential surface of the second seal portion.
9. The shroud assembly of claim 1, wherein the second shroud segment comprises a first circumferential surface and a second circumferential surface spaced along the circumferential direction, wherein the first circumferential edge of the second seal portion is positioned circumferentially between the first circumferential surface of the second shroud segment and the second circumferential surface of the second shroud segment, and wherein the second circumferential edge of the second seal portion is positioned circumferentially between the first circumferential surface of the first shroud segment and the second circumferential surface of the first shroud segment.
10. The shroud assembly of claim 9, wherein the seal comprises:
- a fourth seal portion comprising a first circumferential surface and a second circumferential surface spaced apart along the circumferential direction C from the first circumferential surface, wherein the second circumferential surface of the second shroud segment is positioned circumferentially between the first circumferential surface of the fourth seal portion and the second circumferential surface of the fourth seal portion; and
- a fifth seal portion coupling the second seal portion and the fourth seal portion.
11. The shroud assembly of claim 1, wherein the third seal portion is formed integrally with the first seal portion and the second seal portion.
12. The shroud assembly of claim 1, wherein the seal is planar.
13. The shroud assembly of claim 1, wherein the first seal portion defines an axial length, wherein the second seal portion defines an axial length, wherein the first shroud segment defines an axial length, and wherein the axial length of the first seal portion and the axial length of the second seal portion are at least about half of the axial length of the first shroud segment.
14. A gas turbine engine defining a circumferential direction C, comprising:
- a compressor section;
- a combustion section;
- a turbine section, comprising: a first shroud segment extending between a first end and a second end along the circumferential direction C; a second shroud segment spaced from the first shroud segment along the circumferential direction C and defining a gap with the second end of the first shroud segment; a third shroud segment spaced from the first shroud segment along the circumferential direction C and defining a gap with the first end of the first shroud segment; and a seal comprising: a first seal portion positioned at least partially on the first shroud segment and the third shroud segment and at least partially covering the gap defined by the first shroud segment and the third shroud segment; a second seal portion positioned at least partially on the first shroud segment and second shroud segment and at least partially covering the gap defined between the first shroud segment and the second shroud segment; and a third seal portion extending between and coupling the first seal portion and the second seal portion.
15. The gas turbine of claim 14, wherein the first shroud segment comprises a first circumferential surface at the first end and a second circumferential surface at the second end, wherein the second seal portion comprises a first circumferential edge and a second circumferential edge spaced apart along the circumferential direction C, and wherein the second circumferential surface of the first shroud segment and the first circumferential surface of the second shroud segment are positioned circumferentially between the first circumferential edge of the second seal portion and the second circumferential edge of the second seal portion.
16. The gas turbine engine of claim 15, wherein the first seal portion comprises a first circumferential edge and a second circumferential edge spaced apart along the circumferential direction C from the first circumferential edge, and wherein the first circumferential surface of the first shroud segment is positioned circumferentially between the first circumferential edge of the first seal portion and the second circumferential edge of the first seal portion.
17. The gas turbine engine of claim 16, further comprising:
- a first mounting projection extending radially outwardly from the first shroud segment, wherein the first mounting projection is circumferentially positioned between the second circumferential edge of the first seal portion and the second circumferential edge of the second seal portion; and
- a second mounting projection extending radially outwardly from the second shroud segment, wherein the first circumferential edge of the second seal portion and the second circumferential edge of the second seal portion are circumferentially positioned between the first mounting projection and the second mounting projection.
18. The gas turbine engine of claim 16, wherein the seal comprises:
- a fourth seal portion comprising a first circumferential edge and a second circumferential edge spaced apart along the circumferential direction C from the first circumferential edge, wherein the second circumferential surface of the second shroud segment is positioned circumferentially between the first circumferential edge of the fourth seal portion and the second circumferential edge of the fourth seal portion; and
- a fifth seal portion coupling the second seal portion and the fourth seal portion.
19. The gas turbine engine of claim 18, wherein the first circumferential edge of the first seal portion, the first circumferential edge of the second seal portion, and the first circumferential edge of the fourth seal portion are parallel.
20. The gas turbine engine of claim 18, wherein the third seal portion comprises a first axial edge and second axial edge spaced apart along the axial direction A from the first axial edge, wherein the fifth seal portion comprises a first axial edge and second axial edge spaced apart along the axial direction A from the first axial edge, and wherein the first axial edge of the third seal portion and the first axial edge of the fifth seal portion are coplanar.
Type: Application
Filed: May 16, 2016
Publication Date: Nov 16, 2017
Patent Grant number: 10221712
Inventors: Michael Anthony Ruthemeyer (Cincinnati, OH), David Alan Frey (West Chester, OH)
Application Number: 15/155,115